1. Field of the Invention
This invention relates to cage making apparatus. In particular, it relates to apparatus for making elongate steel cages for reinforced concrete piles, foundations and so forth.
2. Discussion of the Known Art
Steel cages are most typically assembled from steel bands, formers and rings welded to longitudinal bars. Traditionally, assembly of such cages has been a manual fabrication operation. This is a laborious and time-consuming operation that requires extensive preparation, but is still in widespread use. This is in part because there is a requirement that cages be made on-site to a wide range of specifications and configurations, meaning that any system for making cages must be both flexible and transportable if it is to receive widespread acceptance.
There is, therefore, a demand for apparatus that can automate production of cages with a view to reducing time and labor required, while maintaining the flexibility and range of application of manual systems.
One such apparatus known in the art comprises a machine having a rotatable shaft running parallel to a longitudinal axis of the machine that is supported at each end by frames. Towards the ends of the shaft there are provided holding devices for engaging a skeleton cage. In use, the skeleton cage is made on the machine. The holding devices engage the skeleton cage and the shaft is rotated by a motor thereby causing the cage to rotate. Steel wire is wrapped onto the cage from a drum. When the cage has been completed it has to be removed from the machine in a direction parallel to the shaft, i.e., along the longitudinal axis of the machine, because of the configuration of the apparatus, leading to an excessively large apparatus and a need for additional supporting devices to support the weight of the cage. Removing the cage along the length of the machine is a particular problem when a limited space is available for operating the machine. Another limitation of this type or machine is that it can only produce cages having a circular cross-section.
An aim of the current invention is to provide an apparatus that mitigates at least some of the aforementioned problems, and in particular that provides a more compact and integrated cage making apparatus.